(带文稿) 0525：慎点！科学家对恶心心的蟑螂下手了【文末小测】

In this file photo, giant Madagascar hissing cockroaches cling to box before being cremated at Bangkok hospital on May 23, 2003. (Sukree Sukplang)

Transcript

Researchers have developed a new method for making changes to the genes of insects called cockroaches.

The scientists said the method could be an important step. They said it could help remove barriers to researching and changing, or editing, genes of all kinds of insects.

The technology used in the new method is called CRISPR/Cas-9. The CRISPR tool makes it possible for scientists to change DNA by adding or taking away parts of the DNA of living cells. DNA is deoxyribonucleic acid. It is a main substance that carries genetic information in the cells of living things.

CRISPR technology has been used to carry out research and create possible treatments for genetic diseases affecting humans. In 2020, two women were awarded the Nobel Prize in Chemistry for developing the CRISPR/Cas-9 tool.

The method has also been used to target and change genes in animals and insects. Last year, for example, scientists announced they had used the CRISPR/Cas-9 method to block the ability of mosquitos to identify human targets.

The scientists involved in the new study also used the CRISPR/Cas-9 tool. But they developed a new process to improve their research for use with many kinds of insects.

In the past, researchers performing gene editing on insects injected genetically edited materials directly into developing embryos. But the new method involves injecting the materials into female adults as early eggs are still developing.

The researchers call their new method “direct parental” and describe it as “simple and efficient.”

Takaaki Daimon of Japan's Kyoto University helped lead the research and was the lead writer of the study. He said in a statement that with the new method, “researchers have been freed from the annoyance of egg injections.”

Daimon added that the process his team invented simplifies and speeds up gene editing in insects. “We can now edit insect genomes more freely and at will. In principle, this method should work for more than 90 percent of insect species,” he said.

The results recently appeared in the publication Cell Reports Methods.

The researchers said cockroaches and many other kinds of insects have unusual reproductive systems. This limits the way the CRISPR editing technology can be used on them. Past attempts that sought to edit the genes of cockroaches failed.

The team said it solved the problem by creating a method that does not require CRISPR materials to be injected into early embryos.

The result successfully created so-called “knockout” cockroaches. The term “knockout” is used by scientists to describe organisms that have had all or part of a gene removed or inactivated by genetic engineering.

In addition, the scientists tested their method on red flour beetles. Those experiments produced results more than 50 percent of the time, the team reported in the study.

The researchers said their results demonstrated that the new method can be used in research involving many kinds of insects. But they noted the process will not work on some kinds of insects that have more complex reproductive systems, such as fruit flies.

The team said their method does not require costly equipment, complex experimental setups or highly skilled laboratory workers. Daimon said, “These problems with (traditional) methods have plagued researchers who wish to perform genome editing on a wide variety of insect species.”

I’m Bryan Lynn.

What kind of organism has CRISPR technology been used on?

A. Animals
B. Humans
C. Insects
D. All of the above

What did the researchers predict about the ability of their method to work with other kinds of insects?

A. The method is likely not effective in most insect species.
B. The method only works on insects within the cockroach family.
C. The method should work for most kinds of insect species.
D. The method should work for 100 percent of insect species.

What does the term “knockout” describe?

A. Organisms that are genetically engineered to “knock out” undesired forms of the same species

B. Organisms that have had all or part of a gene removed or inactivated by genetic engineering

C. Organisms that have been completely created with CRISPR technology inside a laboratory

D. Organisms that have been genetically engineered to resist specific kinds of disease

What is one way the researchers said their process is an improvement over traditional methods?

A. It can be performed on all kinds of insects.

B. It does not require highly skilled laboratory workers.

C. It does not require the CRISPR/Cas-9 editing tool.

D. All of the above

Words in This Story

efficient – adj. working well and not wasting time or energy

annoyed – adj. angry or upset

genome – n. the complete set of genetic material of a human, animal, plant, or other living thing

principle – n. a basic idea or rule that explains or controls how something happens or works

plague – v. to cause worry, pain or difficulty to someone or something over a period of time

species – n. a group of animals or plants that are similar and can produce young animals or plants

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